package JVM;

public class HeapSpaceInitial {
    public static void main(String[] args) {
        //返回 Java虚拟机的堆内存总量
        long initialMemory = Runtime.getRuntime().totalMemory() / 1024 / 1024;
        //返回 Java虚拟机试图使用的最大堆内存量
        long maxMemory = Runtime.getRuntime().maxMemory() / 1024 / 1024;

        System.out.println("-Xms:" + initialMemory + "M");
        System.out.println("-Xmx:" + maxMemory + "M");
        System.out.println("系统内存大小为：" + initialMemory * 64.0 / 1024 + "G");
        System.out.println("系统内存大小为：" + initialMemory * 4.0 / 1024 + "G");

        try {
            Thread.sleep(1000000000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}